#include<stdio.h>
#include<stdlib.h>

int main()
{
    int score;
    printf("请输入一个百分制成绩\n");
    scanf ("%d",&score);
    if(score>=90 && score<=100)
        printf("A\n");
    else if(score>=80&&score<90)
        printf("B\n");
    else if(score>=70 && score<80)
        printf("C\n");
    else if(score>=60 && score<70)
        printf("D\n");
    else if(score>=0 && score<60)
        printf("E\n");
    else
        printf("input error\n");
    
    system("pause");
    return 0;
}